In an image processing device composed such that it can display a prescribed object whilst changing the shape of the object. Furthermore, the image processing device includes a first memory for recording information for first polygons which form the object; a second memory for recording information for second polygons that form the object and are linked to the first polygons; and when the shape of the object is changed, the shapes of the second polygons are changed such that no gaps are produced between the first polygons and the second polygons. Using computer graphics in a video game it is possible to achieve a more realistic object representation, wherein joint regions move in a natural manner.